The main components of undersea cables are a core which contains at least one optical fibre and which is surrounded by a network of wires referred to as a carrier vault which provides mechanical strength to the assembly. These cables are submerged, sometimes to great depths, and are therefore subject to high hydrostatic pressures.
Sometimes, therefore, a cable may break and it is therefore necessary to be able to connect the two lengths together again so as to re-establish continuity of the assembly. It may also be necessary to connect two cables together. Known methods do not allow such connection to be performed sufficiently reliably. Preferred implementation of the present invention provide a practical method of connecting together optical fibre undersea cables which may be submerged to great depths.